Reappraisal of the Identity of Batrachium pekinense (Ranunculaceae) and Its Implication for Biodiversity Conservation and Management

Because of human-induced habitat deterioration and climate change, a large number of species are threatened and even endangered. Batrachium pekinense Liang Liu, a perennial aquatic plant endemic to Beijing, was synonymized as a widely distributed species in Northern China, B. bungei Steudel, but it was later listed in the national key protected wild plants in China. Taxonomic uncertainty should be clarified especially when related species may be allocated with a limited conservation budget. In this study, we reappraised the identity of B. pekinense based on results from molecular phylogenetic analysis and 15-year field observations. Our result shows that 77% of the 65 individuals collected from various sites share identical sequences in both the nuclear ribosomal ITS and the plastid psbA-trnH markers, all samples of the two species consist of one monophyletic clade with strong support, and continuous morphological variations on the key distinguishing character, the leaf shape, are observed in the field. Integrative evidence from both our and the others’ studies supports the same identity for B. pekinense and B. bungei. Hence, we suggest excluding B. pekinense from the list of national key protected wild plants of China in its next update and advocate the integrative evidence-based taxonomy and systematics for biodiversity conservation and management.